Here's a secret: I prefer regular soda to diet. I know: empty calories. I should drink water instead. And I do, usually. For me, soft drinks are a treat, and I don't like the taste of artificial sweeteners. Before the empty-calorie police haul me away, though, please tell them I can count the number of sodas I drink in an entire year on one hand. Like I said, they're a treat.

But for many of us, sugary drinks are almost another food group. People enjoy sodas all over the world, but no one loves soft drinks quite as much as Americans do. We consumed nearly 50 gallons each, on average, last year, according to Beverage Digest.

Of course, in an obesity epidemic, when drinks are served in cups as big as buckets, soft drinks are an easy target. But here's where current nutrition thinking about sweet beverages takes a twist: Sodas aren't the only source of liquid sugar that many health experts would like to see drastically reduced in our diet. If you think sugar-sweetened beverages (SSBs) don't include virtuous-sounding agave-sweetened teas or 100-percent natural fruit juices, you're wrong. Nutritional research on the effects of SSBs looks at any beverage containing more than a threshold amount of sugar. That puts orange juice, with its 2.4 grams of naturally occurring sugar per ounce, in the lineup with 4-gram-per-ounce orange soda.

Fruit juice in the same category as soda? This is the sort of generalizing that happens when foods are reduced to nutrient profiles. The truth is that SSBs, like cookies, cakes, or other sweet nothings, aren't inherently bad. But consuming too much of them is.

Studies have essentially linked SSB consumption to weight gain, which in part may be due to the fact that liquid calories go down so easily—so easily that we do a bad job of cutting back elsewhere in our diets to compensate for the extra calorie intake.

But the harm likely comes from more than just the calories. Research indicates that a steady stream of liquid sugar can wreak havoc on your body. According to Lilian Cheung, DSc, RD, Director of Health Promotion and Communication at Harvard's School of Public Health, "Drinking sugary beverages on a regular basis is associated with an increased risk of becoming overweight or obese, developing diabetes and possibly high blood pressure, unfavorable blood lipid profiles, inflammation, and heart disease."

Big gulp, indeed: The relationship of SSB consumption to type 2 diabetes and heart disease risks may come from sources other than simple weight gain. That's because research has shown that diets with high sugar loads are associated with increased insulin resistance, which can set the stage for diabetes, as well as increased levels of inflammatory markers that are known to raise chronic disease risks. (Inflammation may affect arterial plaque buildup and clots, which can lead to heart disease and stroke.)

Consumption of SSBs may be especially bad for women. During a 22-year evaluation as part of the Nurses' Health Study, more than 88,000 women self-reported their SSB intakes. When lifestyle and other dietary factors were accounted for, the results showed that as few as two high-sugar drinks daily correlated with higher heart disease risk.

Where does this leave us? A simplistic approach can lead quickly to File-Under-"Duh" conclusions like this one, published last year in a study in Archives of Pediatrics & Adolescent Medicine: "Replacing sugar-sweetened beverage intake with water is associated with reductions in total calories." Well, yes. Meanwhile, the more sophisticated whole-foods approach to nutrition will lead us to conclude we're better off eating a whole orange to get our vitamins and minerals (and fiber) rather than drinking nutrients from orange juice.

Both conclusions are true, and one is a reasonable guide to healthy eating: I advocate the whole-food approach in general. But strict rule-making is boring. We can live by water alone, but we may not enjoy it, and orange juice rounds out a healthy breakfast nicely.

I vote, as usual, for balance. Must you drink water and only water? No. Are you wise to let water and other calorie-free beverages form the bulk of your daily fluid intake? Yes. The list also includes tea, coffee, sparkling and flavored waters, and diet beverages with non-nutritive sweeteners, if you like.

Nor is full-sugar soda "banned." But beware of the lure of the sweetened drink: the calories that are so easy to forget, and the role that too much liquid sugar may play in some not-so-healthy outcomes.